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Penile Raphe
The penile raphe is a visible line or ridge of tissue that runs on the ventral (urethral) side of the human penis beginning from the base of the shaft and ending in the prepuce between the penile frenulum. The line is typically darker than the rest of the shaft skin, even though its shape and pigmentation may vary greatly among males. The penile raphe is part of a broader line in the male reproductive organs, that runs from the anus through the perineum (perineal raphe) and continues to the scrotum and penis, collectively referred to as median raphe. The penile raphe along with the skin between it are homologous to the female labia minora. The line consists of a subcutaneous fibrous plate, which may vary in prominence and thickness in various areas of the genitals. In the scrotum, the line is located over the internal scrotal septum that divides the two sides of the sac and is densely occupied by nerve fibers. The raphe may become more prominent and darker when the scrotal s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Urogenital Folds
The development of the reproductive system is the part of embryonic growth that results in the sex organs and contributes to sexual differentiation. Due to its large overlap with development of the urinary system, the two systems are typically described together as the genitourinary system. The reproductive organs develop from the intermediate mesoderm and are preceded by more primitive structures that are superseded before birth. These embryonic structures are the mesonephric ducts (also known as ''Wolffian ducts'') and the paramesonephric ducts, (also known as ''Müllerian ducts''). The mesonephric duct gives rise to the male seminal vesicles, epididymides and vasa deferentia. The paramesonephric duct gives rise to the female fallopian tubes, uterus, cervix, and upper part of the vagina. Mesonephric ducts The mesonephric duct originates from a part of the pronephric duct. Origin In the outer part of the intermediate mesoderm, immediately under the ectoderm, in the re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scrotum
In most terrestrial mammals, the scrotum (: scrotums or scrota; possibly from Latin ''scortum'', meaning "hide" or "skin") or scrotal sac is a part of the external male genitalia located at the base of the penis. It consists of a sac of skin containing the external spermatic fascia, testicles, epididymides, and vasa deferentia. The scrotum will usually tighten when exposed to cold temperatures. The scrotum is homologous to the labia majora in females. Structure In regards to humans, the scrotum is a suspended two-chambered sac of skin and muscular tissue containing the testicles and the lower part of the spermatic cords. It is located behind the penis and above the perineum. The perineal raphe is a small, vertical ridge of skin that expands from the anus and runs through the middle of the scrotum front to back. The scrotum is also a distention of the perineum and carries some abdominal tissues into its cavity including the testicular artery, testicular vein, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Human Male Reproductive System
The male reproductive system consists of a number of sex organs that play a role in the process of human reproduction. These organs are located on the outside of the body, and within the pelvis. The main male sex organs are the penis and the scrotum, which contains the testicles that produce semen and sperm, which, as part of sexual intercourse, fertilize an ovum in the female's body; the fertilized ovum (zygote) develops into a fetus, which is later born as an infant. The corresponding system in females is the female reproductive system. External genitalia Penis The penis is an intromittent organ with a long shaft, an enlarged bulbous-shaped tip called the glans and its foreskin for protection. Inside the penis is the urethra, which is used to ejaculate semen and to excrete urine. Both substances exit through the meatus. When a male becomes sexually aroused, erection occurs because sinuses within the erectile tissues of the penis ( corpora cavernosa and corpus spon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Raphe
Raphe ( ; from ;Liddell, H.G. & Scott, R. (1940). ''A Greek-English Lexicon. revised and augmented throughout by Sir Henry Stuart Jones. with the assistance of. Roderick McKenzie.'' Oxford: Clarendon Press. : raphae or raphes) has several different meanings in scientific terminology. In botany and planktology, it is commonly used when describing a seam or ridge on diatoms or seeds. In animal anatomy, it is used to describe a ridged union of continuous biological tissue. There are several different significant anatomical raphes: * The raphe nucleus is a moderate-size cluster of nuclei found in the brain stem that releases serotonin to the rest of the brain. Selective serotonin reuptake inhibitor (SSRI) antidepressants are believed to act at these nuclei. * The buccal raphe, which is on the cheek and evidence of the fusion of the maxillary and mandibular processes * The lingual raphe on the tongue. Obvious physical evidence of the lingual raphe includes the frenulum (also c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Development Of The Reproductive System
The development of the reproductive system is the part of embryonic growth that results in the sex organs and contributes to sexual differentiation. Due to its large overlap with development of the urinary system, the two systems are typically described together as the genitourinary system. The reproductive organs develop from the intermediate mesoderm and are preceded by more primitive structures that are superseded before birth. These embryonic structures are the mesonephric ducts (also known as ''Wolffian ducts'') and the paramesonephric ducts, (also known as ''Müllerian ducts''). The mesonephric duct gives rise to the male seminal vesicles, epididymides and vasa deferentia. The paramesonephric duct gives rise to the female fallopian tubes, uterus, cervix, and upper part of the vagina. Mesonephric ducts The mesonephric duct originates from a part of the pronephric duct. Origin In the outer part of the intermediate mesoderm, immediately under the ectoderm, in the re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Labioscrotal Swelling
The labioscrotal swellings (genital swellings or labioscrotal folds) are paired structures in the mammalian embryo that represent the final stage of development of the caudal end of the external genitals before sexual differentiation. In humans, the two swellings merge: * In the ''female'', they become the posterior labial commissure. The sides of the genital tubercle grow backward as the genital swellings, which ultimately form the labia majora; the tubercle itself becomes the mons pubis. * In the ''male'', they become the scrotum In most terrestrial mammals, the scrotum (: scrotums or scrota; possibly from Latin ''scortum'', meaning "hide" or "skin") or scrotal sac is a part of the external male genitalia located at the base of the penis. It consists of a sac of skin .... References External links "Development of Male External Genitalia", at mcgill.caDiagram at mhhe.com* * {{Authority control Embryology of urogenital system ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nerve
A nerve is an enclosed, cable-like bundle of nerve fibers (called axons). Nerves have historically been considered the basic units of the peripheral nervous system. A nerve provides a common pathway for the Electrochemistry, electrochemical nerve impulses called action potentials that are transmitted along each of the axons to peripheral organs or, in the case of sensory nerves, from the periphery back to the central nervous system. Each axon is an extension of an individual neuron, along with other supportive cells such as some Schwann cells that coat the axons in myelin. Each axon is surrounded by a layer of connective tissue called the endoneurium. The axons are bundled together into groups called Nerve fascicle, fascicles, and each fascicle is wrapped in a layer of connective tissue called the perineurium. The entire nerve is wrapped in a layer of connective tissue called the epineurium. Nerve cells (often called neurons) are further classified as either Sensory neuron, sens ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scrotal Septum
The septum of scrotum or scrotal septum is an incomplete vertical wall (septum) that divides the scrotum into two compartments –each containing a single testis. It consists of flexible connective tissue and nonstriated muscle (dartos fascia The dartos fascia, dartos tunic or simply dartos is a layer of connective tissue found in the penile shaft, foreskin and scrotum. The penile portion is referred to as the superficial fascia of penis or the subcutaneous tissue of penis, while the ...). The site of the median septum is apparent on the surface of the scrotum along a median longitudinal ridge called the scrotal raphe. The perineal raphe further extends forward to the undersurface of the penis and backward to the anal opening. The purpose of the median septum is to compartmentalize each testis in order to prevent friction or trauma. The scrotal skin is vascularized via the two external pudental arteries and the internal pudental artery. The central territory of the scrotum ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fiber
Fiber (spelled fibre in British English; from ) is a natural or artificial substance that is significantly longer than it is wide. Fibers are often used in the manufacture of other materials. The strongest engineering materials often incorporate fibers, for example carbon fiber and ultra-high-molecular-weight polyethylene. Synthetic fibers can often be produced very cheaply and in large amounts compared to natural fibers, but for clothing natural fibers have some benefits, such as comfort, over their synthetic counterparts. Natural fibers Natural fibers develop or occur in the fiber shape, and include those produced by plants, animals, and geological processes. They can be classified according to their origin: * Vegetable fibers are generally based on arrangements of cellulose, often with lignin: examples include cotton, hemp, jute, flax, abaca, piña, ramie, sisal, bagasse, and banana. Plant fibers are employed in the manufacture of paper and textile ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Labia Minora
The labia minora (Latin for 'smaller lips', : labium minus), also known as the inner labia, inner lips, or nymphae, are two flaps of skin that are part of the primate vulva, extending outwards from the inner Vagina#Vaginal opening and hymen, vaginal and Urethral meatus, urethral openings to encompass the Vulval vestibule, vestibule. At the glans clitoridis, each labium splits, above forming the clitoral hood, and below the frenulum of the clitoris. At the bottom, the labia meet at the ''labial commissure''. The labia minora vary widely in size, color and shape from individual to individual. The labia minora are situated between the labia majora and together form the labia. The labia minora are Homology (biology), homologous to the penile raphe and ventral penile skin in males. Structure and functioning The labia minora extend from the clitoris obliquely downward, laterally, and backward on either side of the vulval vestibule, ending between the bottom of the vulval vestibule and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Homology (biology)
In biology, homology is similarity in anatomical structures or genes between organisms of different taxa due to shared ancestry, ''regardless'' of current functional differences. Evolutionary biology explains homologous structures as retained heredity from a common descent, common ancestor after having been subjected to adaptation (biology), adaptive modifications for different purposes as the result of natural selection. The term was first applied to biology in a non-evolutionary context by the anatomist Richard Owen in 1843. Homology was later explained by Charles Darwin's theory of evolution in 1859, but had been observed before this from Aristotle's biology onwards, and it was explicitly analysed by Pierre Belon in 1555. A common example of homologous structures is the forelimbs of vertebrates, where the bat wing development, wings of bats and origin of avian flight, birds, the arms of primates, the front flipper (anatomy), flippers of whales, and the forelegs of quadrupedalis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perineal Raphe
The perineal raphe is a visible line or ridge of tissue on the body that extends from the anus through the perineum to the scrotum (male) or the vulva (female). It is found in both males and females, arises from the fusion of the urogenital folds, and is visible running medial through anteroposterior, to the anus where it resolves in a small knot of skin of varying size. In males, this structure continues through the midline of the scrotum (scrotal raphe) and upwards through the posterior midline aspect of the penis ( penile raphe). It also exists deeper through the scrotum where it is called the scrotal septum. It is the result of a fetal developmental phenomenon whereby the scrotum and penis close toward the midline and fuse. See also * Embryonic and prenatal development of the male reproductive system in humans * Frenulum of penis * Linea nigra * Raphe Raphe ( ; from ;Liddell, H.G. & Scott, R. (1940). ''A Greek-English Lexicon. revised and augmented throughout by Sir He ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
